<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<style type="text/css">

#side {
	background: #39C;
	width: 200px;
	height: 300px;
	float: left;
}
#main {
	background: #0FC;
	height: 300px;
	/*margin:0 200px;*/
	text-align: center;
}
#side_right {
	background: #9C3;
	width: 200px;
	height: 300px;
	float: right;
}
#content {
	width: 800px;
	margin: 0 auto;
}
</style>
</head>

<body>
<div id="content">
  <div id="side">此处显示  id "side" 的内容</div>
  <div id="side_right">此处显示  id "side_right" 的内容</div>
  <div id="main">此处显示  id "main" 的内容</div>
</div>
</body>
</html>
